Try Marapets: flash games, fully customizable characters, quests, missions, item/pet trading, battles, fashion contests, giveaways, prizes, tons of free stuff, friends, forums, chat, blogs, clubs,...
you could also type "what are some free virtual worlds?" I'll answer your question though. There is imvu.com, fantage.com, mcworld.com (if you get a toy from mcdonalds in a happy meal girls get a...
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